A new report on the botched Fast and Furious operation that has landed Attorney General Eric Holder on the hot seat alleges that contrary to popular belief, the Bureau of Alcohol, Tobacco, Firearms and Explosives never meant to allow guns into the hands of Mexican drug cartels.

The lengthy story, published Wednesday by Fortune after a six-month investigation, claims that according to law-enforcement agents directly involved in the operation, ATF did not intentionally let arms cross the U.S.-Mexico border so they could end up in the hands of criminals on the other side.

“They insist they never purposefully allowed guns to be illegally trafficked. Just the opposite: They say they seized weapons whenever they could but were hamstrung by prosecutors and weak laws, which stymied them at every turn,” the report says.

Featured prominently in the story is Dave Voth, a former Fast and Furious supervisor for the ATF who came under fire in 2011 when an agent publicly accused supervisors of ordering subordinates to purposefully refrain from seizing weapons in the hopes that the guns could lead them to criminals. One such gun has been linked to the death of U.S. Border Patrol agent Brian Terry.

The story charges that “the public case alleging that Voth and his colleagues walked guns is replete with distortions, errors, partial truths, and even some outright lies,” and accuses some lawmakers, including House Oversight Committee Chairman Darrell Issa (R-Calif.), of seizing on and amplifying the initial allegations to “score points” against the Obama administration.

“Republican senators are whipping up the country into a psychotic frenzy with these reports that are patently false,” Linda Wallace, a special agent with the Internal Revenue Service’s criminal investigation unit who was assigned to the Fast and Furious team, told Fortune.

An Oversight Committee spokesman repudiated the claims made in the article, calling the story “a fantasy made up almost entirely from the accounts of individuals involved in the reckless tactics that took place in Operation Fast and Furious.”

“It contains factual errors — including the false statement that Chairman Issa has called for Attorney General Holder’s resignation — and multiple distortions,” the spokesman said Wednesday afternoon. “It also hides critical information from readers — including a report in the Wall Street Journal — indicating that its primary sources may be facing criminal charges.”

The official said that congressional aides gave Fortune a number of examples of “false statements” made by the story’s primary source, and that the publication failed to explain details of these alleged errors to readers.

The spokesman added, “The one point of agreement the Committee has with this story is its emphasis on the role Justice Department prosecutors, not just ATF agents, played in guns being transferred to drug cartels in Mexico. The allegations made in the story have been examined and rejected by congressional Republicans, Democrats, and the Justice Department.”

The report comes as the House prepares to vote on holding Holder in contempt of Congress for refusing to turn over some documents in the Fast and Furious investigation. The embattled attorney general has called the failed gun-walking operation “deeply flawed” and maintained that his department put an end to the program — a claim that seems to be at odds with the core of the Fortune story: that the ATF never actually intended for guns to end up in the wrong hands.

Fortune’s reporting consisted of reviews of some 2,000 pages of confidential ATF documents and interviews with dozens of people, including seven law-enforcement agents that were directly involved in the controversial program.